Dashboard lamp-socket.



E. S. PRESTON. msHBoArm 'LAMP SOCKET.

APPLICATION FILED MAYZS. Nil.

1 265,5 1 3. Bat/enwd May 7, 1918.

2 SHEETS-SHEET I.

I I: Er/MarJJ. Ra t '09,

E. S. PRESTON.

DASHBOARD LAMP SOCKET.

APPLICATION FILED mwzs. m1.

1 ,265 .5 1 3. Patented May 7, 1918 2 SHEETS-SHEET 2- fa n ara cifiejfoy Z0 00:

UNITED STATES PATENT OFFICE.

EDWARD S. PRESTON, OF CHICAGO, ILLINOIS.

DASHBOARD LAMP-SOCKET.

Application filed May 23, 1917.

To all whom itmay concern:

Be it known that I, Enwann S. PRESTON, citizen of the United States. residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Dashboard Lamp- Sockets; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to sockets for electric lamps, and in its general aspects aims to provide a socket in which the lamp circuit may be temporarily closed by the bodily movement of one of the socket parts with respect to the remainder of the socket. More particularly, it relates to a lamp lighting system and aims to provide a socket which will enable the circuit to be closed independently by either of two switching means, one of which can be manipulated at the socket, and which may be embodied either with or without a grounding of the circuit to metal parts of the socket. So also, my invention aims to provide a lamp socket in which the circuit to the lamp may be temporarily closed by moving,' a socket portion associated with the lamp, as, for example. a hood or reflector partially housing the lamp.

In' automobile practice. it has long been customary to mount a lamp on the clashboard in front of the chaufl'enr. so as to illuminate the speedometer, the safety lock, etc. this lamp being commonly supplied with current from a storage battery. It has also been customary to use this lamp as an indicator for the effective operation of the oil pump, by connecting the lamp in a circuit which will be automatically closed when oil is forcibly circulated, but which will be opened when the pump stops. 7 While this check on the proper working of the oil pump has been satisfactory in many ways, it involvesa darkening of the dashboard when the engine and pump are shut down, thus making it diflicult for the driver of the vehicle to find the keyhole of his safety look after dark. To overcome objections of this general order, my invention aims to provide a lamp socket suitable for a circuit controlled by the oil supply. but one in which the lamp circuit may also be temporarily closed by a simple manipulation of the lamp bulb or some socket part associated therewith, as for example by pressure on the Specification of Letters Patent.

Patented May '7, 1918.

Serial No. 170,419.

reflecting hood commonly used over a dashboard lamp. In other words, I aim to pro' vide a socket equip ed with twin circuit portions, one of WhlC portions is controlled by a manipulation of a certain socket part.

In accomplishing the purposes of my invention, I may employ socalled double-pole lamps in connection with circuits entirely insulated from the metal parts of the socket; or, I may ground one terminal of the circuit to certain metal socket parts and employ a socalled single-pole socket construction. Both of these embodiments are shown in the accompanying drawings and described in the following specification, from which further objects of my invention will appear.

In the drawings, Figure 1 is a central longitudinal section through a double-pole socket embodying my invention.

Fig. 2 is an enlarged transverse section, taken along the line 2-2 and looking to the left in Fig. 1.

Fig. 3 is a similar section taken from line 33 and looking toward the right in Fig. 1.

Fig. 4 is a diagrammatic view of a pump and socket circuit employing the socket of Fig. 1.

Fig. 5 is a central longitudinal section through a single-pole or grounded shell dashboard lamp socket embodying my invention.

Fig. 6 is a transverse section through the same, looking forward from the line 6-6 in Fig. 5.

Fig. 7 is a diagram showing the circuit connections as used with the socket of Fig. 7.

In the embodiment of Fig. 1, the socket of my invention includes an outer casing 1 or holder, here shown as secured to a dashboard 2. in which casing or'holder an inner shell 3 is slidably mounted but limited in movement by suitable means, such as a screw 4 rigid with respect to the shell 3 and sliding in a longitudinal slot 5 in the casingL. The inner shell 3 is equipped at its forward end for interlocking with the base of a lamp 6 (as by bayonet slots 7 engaging pins 8 on the lamp base), which lamp has the ends of its fi ament connected to terminals 9 on the lamp base. Continuouslyengaging the respective terminals 9 of the lamp are conducting members 10 and 11 carried by an" insulating body 12 mounted in the inner shell 3, each of which members desirab y consists of a cylinder carrying a spri P pressed plunger after the manner common f nceted to the switch 21. when the oil is under pressure, the battery in sockets for automobile lamps. Both of the conducting members and 11 extend to the rear end of the insulator 12 and one of the same (in this case the member 11) carries a plate 13 for extending its exposed rear surface as shown in Fig. 3.

Fast Within the rear end of the outer casing 1 is an insulating plug 14 carrying terminals for three wires 15, it and 17 each of whicl'i terminals also consists desirably ci a: metal cylinder carrying a spring-pressed plunger extending forwardly beyond the plug li and toward the conducting members 10 and 11. Two of these terminals, viz. the ones associated with the wires 15 and 17 have plungers of such length as normalty-to contact respectively with the member 10 and the plate 13, while the plunger 18 on the terminal associated with the wire 16 is in alinement with another portion of the plate 13 but too short to contact with he latter when the inner shell 3 and the e e ments carried by the latter are in the position of Fig. 1.

In using the socket. ot' Fig. 1 for thc purpose mentioned. the wires 15 and 16 are con nected to the terminals of a source of electrieity, such as a battery 19, while the wire 17 leads to the terminal 20 of a switch 21 arranged for electrically connecting the wires 16 and 17 as shown in Fig. 4, this switch being closed by the upward pressure of oil 22 in a cylinder on a piston 24 con- Consequently,

\ circuit to the lamp is closed through the {wires 15 and 17. However, if the oil pump sfto is or ceases to create. the pressure for vhich the piston 24 is adjusted, the switch or drops to the position shown in dotted incs, thereby extinguishing the lamp. Now, if the light of the lamp is needed before the tminp is restarted (as for example, for findng the keyhole in a safety lock mounted on the dashboard), the sliding shell 3 of the socket. is pressed toward the rear against the resistance of the springs in the conducting members, until the plate 13 contacts with the short plunger 18. This closes the battery circuit. through the wires 15 andlti, so that the lamp will burn as long as the sliding shell 3 is pressed inward, but will go out again when the pres-lure, is released. In other words, the lndily .iiovement of the slid ably mounted portion of the socket. serveii to establieh 1. shunt around the circuit portioii comprising the switch 21, the wire 17 an the terminal associated with the latter. T, prevent an overstraining of the springs a sociated with the plungers. I desirab y rovide means for limiting the inward sliding of the shell 3, such as the shoulders 27 cnthis shell or a slot end arranged for an aging the screw 4. I {1190 desir bly) provi e a reflecting hood 26 partially inclosing the lamp and mounted on the shell 3 so that the manual pressure may conveniently be exerted a ainst this hood without touching and per aps soiling the lam I owever, while I have described my inven tion in connection with a socket having all parts of the circuit insulated from the metal socket parts and employing a socalled double-pole lamp, I do not wish to be limited to these or other details of the construction, urpose and arrangement above disclosed, it

eing obvious that the same might be modified in many ways without. departing from the spirit of my invention. For example Fig. 5 shows a socket having the wire 15 grounded to the outer casing and hence to the shell 27 on the lamp base which forms one terminal of the lamp, while the other lamp terminal 28 contacts with a single 35 plunger 29 carried by a conducting member 30 mounted in an insulator 31 which is fast in the inner shell. The conducting member 30 terminates at. its rear in a plate 32 normally contacting only with the longer of two spring-pressed plungers carried by the terminals of the wires 16 and 17, which terminals are mounted in an insulating plug 33 fast within the outer casing 1. In this case, the battery circuit is :ormally closed through the switch'and the wire 17, but may be closed through the switch-shunting wire 16 and the short plunger associated with the latter by bodily moving the lamp and the substantially T-shaped single interme- 00 diary conducting element toward the plangers, as shown in Fig. 7.

In either case. it will be obvious that my invention provides two paths for a portion of a circuit, which two paths can be inde- 1 5 pendently controlled by separate switching means, and neither of which switching means interferes with the efiectiveness of the other. By constructing the socket of two relatively movable parts, I am able to 1 0 provide the needed auxiliary switching means without the expense and inconven ience of a separate switch; and by utilizing the springs of the contact plungers for normally pressing the slidablc socket portion outwardly, I avoid the expense and space involved by using separate spring means for this purpose. Consequently, I am able to provide the additional feature of a manually operable switch for controlling the lamp without materially adding either to the cost. or the hulkiness of the socket.

I claim as my invention:

1. In a lamp-socket, a pair of relatively movable casing members one of which is inllmlOCkQd with the lamp, a pair of circuit terminals carried by the other casing memher and normally completing the circuit to the lamp, spring means for resisting a relative movement of the casing members in one direction, and an auxiliary circuit terminal connected in shunt with one of the aforesaid terminals and arranged for closing its pottion of the circuit on y upon a relative movgi ment of the casingmembers in the said direction.

2. In a lamp-socket for a circuit having a rupturable and an unrnpturable portion in shunt with each other, a pair of relatively movable casin members one of which is interlocked wit the lamp, sprin means for normally resistin a movement 0 the casing members in one irection, and a pair of circuit terminals carried by the other of the casing members, one of theterminals being connected to the rupturable portion of the circuit and continuously electrically connected to a terminal of the lamp, and theother terminal being connected to the rupturable portion of the circuit and arran ed for affording electrical connection wit the same lamp terminal only upon a relative movement of the casing members in the said di rection.

3. In. an electric fitting, a pair of relatively movable members, a terminal-carrier interlocked with one of said members, a terminal plate associated with the terminalcarrier and connected to one of the terminals of the latter, and a pair of relatively insulated conducting elements carried by the other of said members, one of said elements continuously contacting with said' plate and the other element disposed for contacting with said plate upon relative movement of the said members.

4. In a lampsocket, a pair of relatively movable casing members one of which is interlocked with the lamp, and a pair of circuit terminals of unequal length both connected to the same end of the circuit, the longer of said terminals being arranged for continuously allording electrical connection ilu the lamp and the shorter one for afiording uch connection only upon relative movewith the shorter wire terminal onl ment of the casing members, substantially as and for the purpose described.

5. In a lamp-socket as er claim 4, single spring means operating th for resisting a relative movement of the casing members, and for maintaining the longer terminal continuously in electrical connection with the lamp.

6. In an electric fitting, a casing, a pair of wire terminals of unequal length housed thereby and connected in shunt to a circuit, and yieldin means associated with the casing for ho ding a' lamp in a osition in which it is continuously clectrica yconnected to the longer of the said wire terminals and in which it makes electrical connection upon a bodily movement of the lamp wit respect to the casing.

7-. A lamp socket, including a holder, means carried by-the holder for holding the lamp and permitting a movement of the lamp with respect to the holder, a spring for resisting the said movement, a circuit terminal continuously connected to one terminal of the lamp, and an auxiliary member in shunt with said terminal and arranged ,for affording electrical connection to the same lamp terminal upon a movement of the lamp with respect to the holderagainst the resistance of the spring.

8. In a iamp-socket, a casing, lamp-holding means arranged for permittin a movement of the lamp with respect to the casing, and a pair of circuit terminals both adapted to aflordca'n electrical connection for the same terminal of the lamp, one of said terminals being arranged for continuously afforeling the said connection and the other for affording the same only upon .move' ment of the lamp with respect to the casing.

Signed at. Chicago, Illinois, this 19th day of May, 1917.

- EDWARD s. PREs'roN, 

